text: /*
   * Copyright (C) 2008 Nicolai Haehnle.
   *
   * All Rights Reserved.
   *
   * Permission is hereby granted, free of charge, to any person obtaining
   * a copy of this software and associated documentation files (the
   * "Software"), to deal in the Software without restriction, including
   * without limitation the rights to use, copy, modify, merge, publish,
   * distribute, sublicense, and/or sell copies of the Software, and to
   * permit persons to whom the Software is furnished to do so, subject to
   * the following conditions:
   *
   * The above copyright notice and this permission notice (including the
   * next paragraph) shall be included in all copies or substantial
   * portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
   * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
   * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
   * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
   * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   *
   */
  
  /**
   * @file
   * Utilities to deal with the somewhat odd restriction on R300 fragment
   * program swizzles.
   */
  
  #include "r300_fragprog_swizzle.h"
  
  #include <stdio.h>
  
  #include "../r300_reg.h"
  #include "radeon_compiler.h"
  
  #define MAKE_SWZ3(x, y, z) (RC_MAKE_SWIZZLE(RC_SWIZZLE_##x, RC_SWIZZLE_##y, RC_SWIZZLE_##z, RC_SWIZZLE_ZERO))
  
  struct swizzle_data {
  	unsigned int hash; /**< swizzle value this matches */
  	unsigned int base; /**< base value for hw swizzle */
  	unsigned int stride; /**< difference in base between arg0/1/2 */
  	unsigned int srcp_stride; /**< difference in base between arg0/scrp */
  };
  
  static const struct swizzle_data native_swizzles[] = {
  	{MAKE_SWZ3(X, Y, Z), R300_ALU_ARGC_SRC0C_XYZ, 4, 15},
  	{MAKE_SWZ3(X, X, X), R300_ALU_ARGC_SRC0C_XXX, 4, 15},
  	{MAKE_SWZ3(Y, Y, Y), R300_ALU_ARGC_SRC0C_YYY, 4, 15},
  	{MAKE_SWZ3(Z, Z, Z), R300_ALU_ARGC_SRC0C_ZZZ, 4, 15},
  	{MAKE_SWZ3(W, W, W), R300_ALU_ARGC_SRC0A, 1, 7},
  	{MAKE_SWZ3(Y, Z, X), R300_ALU_ARGC_SRC0C_YZX, 1, 0},
  	{MAKE_SWZ3(Z, X, Y), R300_ALU_ARGC_SRC0C_ZXY, 1, 0},
  	{MAKE_SWZ3(W, Z, Y), R300_ALU_ARGC_SRC0CA_WZY, 1, 0},
  	{MAKE_SWZ3(ONE, ONE, ONE), R300_ALU_ARGC_ONE, 0, 0},
  	{MAKE_SWZ3(ZERO, ZERO, ZERO), R300_ALU_ARGC_ZERO, 0, 0},
  	{MAKE_SWZ3(HALF, HALF, HALF), R300_ALU_ARGC_HALF, 0, 0}
  };
  
  static const int num_native_swizzles = sizeof(native_swizzles)/sizeof(native_swizzles[0]);
  
  /**
   * Find a native RGB swizzle that matches the given swizzle.
   * Returns 0 if none found.
   */
  static const struct swizzle_data* lookup_native_swizzle(unsigned int swizzle)
  {
  	int i, comp;
  
  	for(i = 0; i < num_native_swizzles; ++i) {
  		const struct swizzle_data* sd = &native_swizzles[i];
  		for(comp = 0; comp < 3; ++comp) {
  			unsigned int swz = GET_SWZ(swizzle, comp);
  			if (swz == RC_SWIZZLE_UNUSED)
  				continue;
  			if (swz != GET_SWZ(sd->hash, comp))
  				break;
  		}
  		if (comp == 3)
  			return sd;
  	}
  
  	return 0;
  }
  
  /**
   * Determines if the given swizzle is valid for r300/r400.  In most situations
   * it is better to use r300_swizzle_is_native() which can be accesed via
   * struct radeon_compiler *c; c->SwizzleCaps->IsNative().
   */
  int r300_swizzle_is_native_basic(unsigned int swizzle)
  {
  	if(lookup_native_swizzle(swizzle))
  		return 1;
  	else
  		return 0;
  }
  
  /**
   * Check whether the given instruction supports the swizzle and negate
   * combinations in the given source register.
   */
  static int r300_swizzle_is_native(rc_opcode opcode, struct rc_src_register reg)
  {
  	const struct swizzle_data* sd;
  	unsigned int relevant;
  	int j;
  
  	if (opcode == RC_OPCODE_KIL ||
  	    opcode == RC_OPCODE_TEX ||
  	    opcode == RC_OPCODE_TXB ||
  	    opcode == RC_OPCODE_TXP) {
  		if (reg.Abs || reg.Negate)
  			return 0;
  
  		for(j = 0; j < 4; ++j) {
  			unsigned int swz = GET_SWZ(reg.Swizzle, j);
  			if (swz == RC_SWIZZLE_UNUSED)
  				continue;
  			if (swz != j)
  				return 0;
  		}
  
  		return 1;
  	}
  
  	relevant = 0;
  
  	for(j = 0; j < 3; ++j)
  		if (GET_SWZ(reg.Swizzle, j) != RC_SWIZZLE_UNUSED)
  			relevant |= 1 << j;
  
  	if ((reg.Negate & relevant) && ((reg.Negate & relevant) != relevant))
  		return 0;
  
  	sd = lookup_native_swizzle(reg.Swizzle);
  	if (!sd || (reg.File == RC_FILE_PRESUB && sd->srcp_stride == 0))
  		return 0;
  
  	return 1;
  }
  
  
  static void r300_swizzle_split(
  		struct rc_src_register src, unsigned int mask,
  		struct rc_swizzle_split * split)
  {
  	split->NumPhases = 0;
  
  	while(mask) {
  		unsigned int best_matchcount = 0;
  		unsigned int best_matchmask = 0;
  		int i, comp;
  
  		for(i = 0; i < num_native_swizzles; ++i) {
  			const struct swizzle_data *sd = &native_swizzles[i];
  			unsigned int matchcount = 0;
  			unsigned int matchmask = 0;
  			for(comp = 0; comp < 3; ++comp) {
  				unsigned int swz;
  				if (!GET_BIT(mask, comp))
  					continue;
  				swz = GET_SWZ(src.Swizzle, comp);
  				if (swz == RC_SWIZZLE_UNUSED)
  					continue;
  				if (swz == GET_SWZ(sd->hash, comp)) {
  					/* check if the negate bit of current component
  					 * is the same for already matched components */
  					if (matchmask && (!!(src.Negate & matchmask) != !!(src.Negate & (1 << comp))))
  						continue;
  
  					matchcount++;
  					matchmask |= 1 << comp;
  				}
  			}
  			if (matchcount > best_matchcount) {
  				best_matchcount = matchcount;
  				best_matchmask = matchmask;
  				if (matchmask == (mask & RC_MASK_XYZ))
  					break;
  			}
  		}
  
  		if (mask & RC_MASK_W)
  			best_matchmask |= RC_MASK_W;
  
  		split->Phase[split->NumPhases++] = best_matchmask;
  		mask &= ~best_matchmask;
  	}
  }
  
  struct rc_swizzle_caps r300_swizzle_caps = {
  	.IsNative = r300_swizzle_is_native,
  	.Split = r300_swizzle_split
  };
  
  
  /**
   * Translate an RGB (XYZ) swizzle into the hardware code for the given
   * instruction source.
   */
  unsigned int r300FPTranslateRGBSwizzle(unsigned int src, unsigned int swizzle)
  {
  	const struct swizzle_data* sd = lookup_native_swizzle(swizzle);
  
  	if (!sd || (src == RC_PAIR_PRESUB_SRC && sd->srcp_stride == 0)) {
  		fprintf(stderr, "Not a native swizzle: %08x\n", swizzle);
  		return 0;
  	}
  
  	if (src == RC_PAIR_PRESUB_SRC) {
  		return sd->base + sd->srcp_stride;
  	} else {
  		return sd->base + src*sd->stride;
  	}
  }
  
  
  /**
   * Translate an Alpha (W) swizzle into the hardware code for the given
   * instruction source.
   */
  unsigned int r300FPTranslateAlphaSwizzle(unsigned int src, unsigned int swizzle)
  {
  	unsigned int swz = GET_SWZ(swizzle, 0);
  	if (src == RC_PAIR_PRESUB_SRC) {
  		return R300_ALU_ARGA_SRCP_X + swz;
  	}
  	if (swz < 3)
  		return swz + 3*src;
  
  	switch(swz) {
  	case RC_SWIZZLE_W: return R300_ALU_ARGA_SRC0A + src;
  	case RC_SWIZZLE_ONE: return R300_ALU_ARGA_ONE;
  	case RC_SWIZZLE_ZERO: return R300_ALU_ARGA_ZERO;
  	case RC_SWIZZLE_HALF: return R300_ALU_ARGA_HALF;
  	default: return R300_ALU_ARGA_ONE;
  	}
  }
  